1. Field of the Invention
This invention relates to techniques for shrinking dilatations in the body by localized tissue modification.
2. Related Art
A dilatation is an abnormally enlarged or distended segment of an otherwise patent biological lumen or conduit, such as the gastrointestinal, genito-urinary, pulmonary, vascular, or other systems in the body. Dilatations may also occur at other places within the body, such as in the nervous system, the eyes, or the skin. The degree of enlargement, the length, and the significance of the dilatation may differ greatly between particular dilatations, and is responsive to the nature of the lumen subject to the dilatation. Various etiological factors might be responsible for the development or exacerbation of any particular dilatation; these may include, for example, blockage, stenosis, infection, inflammation, trauma (whether external, internal, or surgical), or cancer. One or more of these factors causes the affected lumen to enlarge, expand or distend, with consequential compromise of the function of the lumen and increased danger of rupture of the lumen.
Treatment of dilatations is aimed at restoration of normal intraluminal diameter and strengthening of the lumen walls. Because of the presence of abnormal or diseased tissue at the dilatation, surgical treatment by endoscopic or by open surgical techniques often poses extra difficulties and has significant morbidity. Moreover, because the tissue of the lumen wall at the dilatation is already diseased, it often generates further scarring and fibrosis when it heals after surgery, which can lead to recurrence of the dilatation.
Accordingly, it would be advantageous to provide a method and system for treatment of dilatations, such as for example vascular aneurysms, which uses existing tissue, which promotes healing of existing tissue, and which helps to prevent recurrence of the dilatation. This advantage is achieved in an embodiment of the invention whereby the dilatation is occluded, a saline solution is introduced into the occluded region and perfused into the lumen-wall tissue of the occluded region, radio frequency (“RF”) or other energy is emitted controllably to heat and soften only the lumen-wall tissue perfused with saline solution in the occluded region of the dilatation, the dilatation is shrunk by application of a chilled saline solution and a vacuum, additional RF or other energy is emitted to ablate, further shrink, and harden only the lumen-wall tissue perfused with saline solution in the occluded region of the dilatation, all without destroying the inner surface of the lumen or other tissues of the body beyond the lumen wall and thereby promoting growth of epithelial cells in the lumen wall.
It would be further advantageous to provide a method and system for treatment of distended, engorged, inflamed or infected tissue such as cysts, gangrenous tissue, necrotic tissue or tumors, including shrinking, reducing, destroying and removing such tissue, from any system of the body including the cardiovascular system, the lymphatic system, the cardiopulmonary system, the gastrointestinal system (head and neck, esophagus, stomach, intestines, colon, rectum), the urogenital system, the nervous system, particular organs such as the kidney or prostate, retinal lesions and skin lesions.